The presence of large bodies of water, such as oceans, seas or large lakes, affects the weather in adjacent westwardly located land masses due to prevailing westerly winds. The effect is illustrated by comparing winter weather conditions between Portland, Oreg., on the west coast of the North American continent and Halifax, Nova Scotia on the east coast; or between Bordeaux, France near the west coast of the European continent with Vladivostok, USSR on the east coast of the Asian continent. Each of these cities is located at approximately 45 degrees north latitude, but winter in the cities on the western coasts of continents is considerably milder than winter in cities on the eastern coasts of continents.
The dominant influence on the climate in the Levantine Basin is the Mediterranean Sea. Winter storms generated over the Mediterranean Sea carry moisture westwardly over Israel, Lebanon, Syria, Turkey and Iran where the moisture precipitates as rain. The area south of the Mediterranean, which is not influenced by winter storms, constitute the world's largest desert areas.
Winter storms in the Mediterranean are generated when cold continental air masses from the north approach the relatively warm sea. The heating of the air mass is the key element for intensive evaporation from the sea and resultant inland precipitation. As the cool air is heated by the relatively warm Mediterranean Sea in wintertime, the air becomes lighter and rises, moving westwardly over the Levant. During winter storms, the Mediterranean Sea gives up heat which had been stored from the summer in the form of the latent of evaporation. The heat stored from the summer in the upper layer of the Mediterranean Sea is the major energy source for winter storms.
A comparision of winter and summer temperature profiles in the Eastern Mediterranean show that in wintertime, the temperature of a column of water forty meters deep in the Mediterranean decreases by some 10 degrees Celsius. This amounts to a net heat flux of about 170 Watts/m.sup.2. During the wintertime, the total solar radiation in flux in this area of the world is about 120 Watts/m.sup.2. Thus, the seasonal heat storage provided by the Mediterranean Sea is the dominant factor that initiates winter storms by which precipitation is spread over the Levantine basin and is the dominant factor establishing the Levant climate.
While there has been consider talk about the weather in the Levantine Basin, very little has been done to increase winter precipitation. It is therefore an object of the present invention to provide a method of and means for modifying weather near continental arid zones.